Question 38934
Well a sector of 36 degrees represents 1/10 of a circle...so the entire circle's area would be 81(pi)...setting that equal to the formula for area, we get
81(pi) = (pi)r^2
r^2 = 81
r = 9
Now the entire circumference is 2(pi)r = 18(pi), but we are talking about only 1/10 of a circle, thus the arc length is 1/10 of 18(pi), or 1.8(pi).